(a) Field of the Invention
This invention relates to a material for absorbing and holding urine. More specifically, it relates to a urine absorbing and holding material which has been rendered reusable by making a polymer of a specific (meth)acrylamide derivative insoluble in water and then combining the water-insolubilized polymer with a fibrous material.
(b) Description of the Prior Art
Diapers have been widely used for many years as materials for absorbing and holding urine. Reflecting the significant prolongation in the average span of human life and the rapid advancement in the medical technology in recent years, there are more and more people who are bedridden or are forced to live with physical handicap such as walking difficulties or hardship. There is a ever-increasing demand for the materialization of welfare society for all people inclusive of such handicapped people.
Specifically speaking, it is desired to allow such people to have life similar to the life style of healthy people. For this purpose, various care or nursing aids, materials, equipment and systems have been developed. However, there are some difficult problems which are still waiting for solutions. As one of such unsolved problems, there is a problem regarding how urination should be dealt with.
Namely, it is a difficult problem for bedridden patients admitted in hospitals or the like how to deal with their urination at night. For those having difficulties or hardship in walking, it is a serious problem how they should deal with sudden desire of urination. This unsolved problem leads to unpleasant feeling after the incontinence of urine. It is also believed to become one of causes for diseases such as cold if the spilled urine is left over especially in winter. To cope with this problem, it has been practiced to spread pads over beds to absorb urine or to use large diapers. Such materials are however not fully satisfactory, because they do not have sufficient urine absorbing and holding capacity and the once-absorbed urine is released by pressures such as users' body weights. It has recently been attempted to enhance the urine absorbing and holding capacity by incorporating a hygroscopic resin such as a water-insolubilized product of a polyacrylate salt in such pads or diapers. Although this approach is certainly effective for enhancing the urine-holding capacity, it is difficult to separate water from the wet resin when the used pads or diapers are used repeatedly. Due to this difficulty, it is practically impossible to use such pads or diapers repeatedly. This means that they have to be thrown away once they have been used, resulting in more expenses for them.